Submarine communications cables can be laid in water, e.g. on the sea floor to provide long-distance communications between continents. For example, a submarine communications cable can include optical fibers to carry (or guide) optical signals representing data. The optical signals can be generated by transmitters converting electrical signal into pulses of light. As a result, an optical fiber of the submarine communications cable can guide an optical signal, or light, corresponding to a portion of the electromagnetic spectrum.
However, optical signals within different portions of the electromagnetic spectrum can interfere with each other, and therefore, a single optical fiber carrying multiple optical signals at different wavelengths (or portions of the electromagnetic spectrum) in the same direction can have issues resulting in needing a reduced span length. For example, optical signals can be provided in the C band or the L band of the electromagnetic spectrum and the optical signals among these different bands can interfere with each other. This results in an increase in a number of amplifiers used to transmit the data across the optical fibers of the submarine communications cable. As a result, the cost of developing and installing a submarine communications cable is increased.
Additionally, submarine communications cables are often designed to be symmetric, and therefore, sized based on the data capacity needed for the dominant direction in which more traffic is expected to be directed. This can also result in an increase in the cost of developing and installing the submarine communications cable.